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Fulltext Factors related to smoking habits of male adolescents

Naing NN, Ahmad Z, Musa R, Hamid FR, Ghazali H, Bakar MH

Tob Induc Dis, 2004 Sep 15;2(3):133-40.
PMID: 19570279 DOI: 10.1186/1617-9625-2-3-133

A cross-sectional study was conducted to identify the factors related to smoking habits of adolescents among secondary school boys in Kelantan state, Malaysia. A total of 451 upper secondary male students from day, boarding and vocational schools were investigated using a structured questionnaire. Cluster sampling was applied to achieve the required sample size. The significant findings included: 1) the highest prevalence of smoking was found among schoolboys from the vocational school; 2) mean duration of smoking was 2.5 years; 3) there were significant associations between smoking status and parents' smoking history, academic performance, perception of the health hazards of smoking, and type of school attended. Peer influence was the major reason students gave for taking up the habit. Religion was most often indicated by non-smokers as their reason for not smoking. Approximately 3/5 of the smokers had considered quitting and 45% of them had tried at least once to stop smoking. Mass media was indicated as the best information source for the students to acquire knowledge about negative aspects of the smoking habit. The authors believe an epidemic of tobacco use is imminent if drastic action is not taken, and recommend that anti-smoking campaigns with an emphasis on the religious aspect should start as early as in primary school. Intervention programs to encourage behavior modification of adolescents are also recommended.
Fulltext Transient severe myocarditis and intraventricular thrombus associated with SARS-CoV-2 vaccination

Loch A, Siew KSW, Tan KL, Azman Bin Raja Aman RRAB

Singapore Med J, 2023 Jun;64(6):366-372.
PMID: 35509213 DOI: 10.11622/smedj.2022042
Fulltext An investigation to offer conclusive recommendations on suitable benefit/cost criteria-based normalization methods for TOPSIS

Krishnan AR, Hamid MR, Tanakinjal GH, Asli MF, Boniface B, Ghazali MF

MethodsX, 2023;10:102227.
PMID: 37333510 DOI: 10.1016/j.mex.2023.102227

Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) is a popular multi-criteria decision-making method that ranks the available alternatives by examining the ideal-positive and ideal-negative solutions for each decision criterion. The first step of using TOPSIS is to normalize the presence of incommensurable data in the decision matrix. There are several normalization methods, and the choice of these methods does affect TOPSIS results. As such, some efforts were made in the past to compare and recommend suitable normalization methods for TOPSIS. However, such studies merely compared a limited collection of normalization methods or used a noncomprehensive procedure to evaluate each method's suitability, leading to equivocal recommendations. This study, therefore, employed an alternate, comprehensive procedure to evaluate and recommend suitable benefit/cost criteria-based normalization methods for TOPSIS (out of ten methods extracted from past literature). The procedure was devised based on three evaluation metrics: the average Spearman's rank correlation, average Pearson correlation, and standard deviation metrics, combined with the Borda count technique.•The first study examined the suitability of ten benefit/cost criteria-based normalization methods over TOPSIS.•Users should combine the sum-based method and vector method into the TOPSIS application for safer decision-making.•The maximum method (version I) or Jüttler's-Körth's method has an identical effect on TOPSIS results.
Dosimetric assessment of Gadolinium-159 for hepatic radioembolization: Tomographic images and Monte Carlo simulation

Musa AS, Abdul Hadi MFR, Hashikin NAA, Ashour NI, Ying CK

Appl Radiat Isot, 2023 Sep;199:110916.
PMID: 37393764 DOI: 10.1016/j.apradiso.2023.110916

A common therapeutic radionuclide used in hepatic radioembolization is yttrium-90 (90Y). However, the absence of gamma emissions makes it difficult to verify the post-treatment distribution of 90Y microspheres. Gadolinium-159 (159Gd) has physical properties that are suitable for therapy and post-treatment imaging in hepatic radioembolization procedures. The current study is innovative for conducting a dosimetric investigation of the use of 159Gd in hepatic radioembolization by simulating tomographic images using the Geant4 application for tomographic emission (GATE) Monte Carlo (MC) simulation. For registration and segmentation, tomographic images of five patients with hepatocellular carcinoma (HCC) who had undergone transarterial radioembolization (TARE) therapy were processed using a 3D slicer. The tomographic images with 159Gd and 90Y separately were simulated using the GATE MC Package. The output of simulation (dose image) was uploaded to 3D slicer to compute the absorbed dose for each organ of interests. 159Gd were able to provide a recommended dose of 120 Gy to the tumour, with normal liver and lungs absorbed doses close to that of 90Y and less than the respective maximum permitted doses of 70 Gy and 30 Gy, respectively. Compared to 90Y, 159Gd requires higher administered activity approximately 4.92 times to achieve a tumour dose of 120 Gy. Thus; this research gives new insights into the use of 159Gd as a theranostic radioisotope, with the potential to be used as a90Y alternative for liver radioembolization.
Malunion of a Floating Knee: Overcoming the Challenges of Extra-articular Deformities With a Robotic-Arm-Assisted Total Knee Arthroplasty

Matheen FIA, Leong JF, Abdul Rani R, Hayyun MF, Mohamad Yahaya NH

Cureus, 2024 Sep;16(9):e68482.
PMID: 39364451 DOI: 10.7759/cureus.68482

Extra-articular deformities (EAD) can pose a challenge to surgeons during a total knee arthroplasty (TKA) surgery. Obtaining an acceptable post-operative hip-knee-ankle (HKA) angle may be difficult, especially in a limb with multiplanar deformities of both the femur and the tibia. Our case is about a 66-year-old gentleman with a long-term deformity of his right lower limb secondary to malunion of the right femoral shaft and tibial shaft fractures. He initially presented with a right floating knee injury, 45 years ago, which was managed with conservative measures. He subsequently presented to us with ipsilateral knee osteoarthritis and underwent a robotic-assisted total knee arthroplasty surgery. Robotic- or computer-assisted total knee arthroplasty is an actively developing area and is gaining popularity among arthroplasty surgeons. In cases with severe extra-articular deformities such as in this case, robotic-assisted surgery can be superior to conventional surgery.
Fulltext A Comparison of the National Cervical Cancer Policies in Six Developing Countries with the World Health Organization Recommendations: A Narrative Review

Amir SM, Idris IB, Said ZM, Yusoff HM, Manaf MRA

Iran J Public Health, 2023 Jun;52(6):1108-1120.
PMID: 37484154 DOI: 10.18502/ijph.v52i6.12952

BACKGROUND: This study reviewed cervical cancer policies implemented in developing countries that adhered to WHO standards. Despite long being known as a preventable disease, cervical cancer is still one of the leading causes of mortality among women. Nine out of ten cervical cancer deaths occurred in less-developed countries, suggesting that the preventive and control approaches in these countries might differ from those in developed nations.
METHODS: Cervical cancer policies in six developing countries from each WHO region were selected while related data from the Cervical Cancer Country Profiles 2021 by WHO were retrieved for comparison.
RESULTS: The cervical cancer policies that were included in this review were from Malaysia, Thailand, Iran, Kenya, Argentina, and Ukraine. According to the latest guidelines on the management of cervical cancers, WHO recommendations have been elaborated on primary, secondary, and tertiary prevention. A comparison of policies among these selected countries showed variation in each level of prevention. The cancer burden in each country was also found to determine the progression of cervical cancer prevention and policy controls in these countries.
CONCLUSION: This review emphasizes the dissimilarities of cervical cancer policies in six developing countries compared to recommendations by the WHO. Identifying these discrepancies could help policymakers in developing nations to recognize the pressing issues surrounding cervical cancer prevention and establish more effective prevention and control approaches.
Fulltext Single nucleotide polymorphisms (SNPs) that are associated with obesity and type 2 diabetes among Asians: a systematic review and meta-analysis

Yanasegaran K, Ng JYE, Chua EW, Nawi AM, Ng PY, Abdul Manaf MR

Sci Rep, 2024 Aug 29;14(1):20062.
PMID: 39209904 DOI: 10.1038/s41598-024-70674-2

Single nucleotide polymorphisms (SNPs) could increase the susceptibility of individuals to develop obesity and type 2 diabetes (T2DM). Obesity and T2DM are closely related pathophysiologically, thus similar SNPs could mediate both these diseases, but this is rarely reported. Furthermore, limited studies have been performed to summarize SNP data in the Asian population compared to the Western population. In this study, we aimed to summarize SNPs that are associated with the development of obesity and T2DM among Asian populations. We searched six literature databases and Review Manager (RevMan) was used for meta-analysis. The pooled odds ratios (ORs) and 95% CIs were calculated with a random effects model for the heterogeneity among studies. The pooled analysis showed that rs9939609 (FTO gene) and rs17782313 and rs571312 (MC4R gene) are associated with obesity with an odd ratio (OR) of 1.37, 1.36 and 1.29 respectively. For T2DM, five SNPs, rs7903146 and rs12255372 (TCF7L2 gene), rs13266634 and rs11558471 (SLC30A8 gene) and rs2283228 (KCNQ1 gene) have also shown strong associations with T2DM at OR of 1.64, 1.61, 1.22, 1.29 and 1.60 respectively. This data could be used to develop a gene screening panel for assessing obesity and T2DM susceptibility.
Fulltext Influence of Woven Glass-Fibre Prepreg Orientation on the Flexural Properties of a Sustainable Composite Honeycomb Sandwich Panel for Structural Applications

Amir AL, Ishak MR, Yidris N, Zuhri MYM, Asyraf MRM, Zakaria SZS

Materials (Basel), 2023 Jul 15;16(14).
PMID: 37512295 DOI: 10.3390/ma16145021

Owing to the high potential application need in the aerospace and structural industry for honeycomb sandwich composite, the study on the flexural behaviour of sandwich composite structure has attracted attention in recent decades. The excellent bending behaviour of sandwich composite structures is based on their facesheet (FS) and core materials. This research studied the effect of woven glass-fibre prepreg orientation on the honeycomb sandwich panel. A three-point bending flexural test was done as per ASTM C393 standard by applying a 5 kN load on different orientation angles of woven glass-fibre prepreg honeycomb sandwich panel: α = 0°, 45° and 90°. The results show that most of the sandwich panel has almost the same failure mode during the three-point bending test. Additionally, the α = 0° orientation angle shows a higher maximum load prior to the first failure occurrence compared to others due to higher flexibility but lower stiffness. In addition, the woven glass-fibre prepreg orientation angle, α = 0°, has the maximum stress and flexural modulus, which directly depend upon the maximum load value obtained during the flexural test. In addition, the experimental results and analytical prediction for honeycomb sandwich deflection show good agreement. According to the result obtained, it is revealed that woven glass-fibre honeycomb sandwich panels with an α = 0° orientation is a good alternative compared to 45° and 90°, especially when better bending application is the main purpose. The final result of this research can be applied to enhance the properties of glass-fibre-reinforced polymer composite (GFRPC) cross-arm and enhance the existing cross-arm used in high transmission towers.
Fulltext Rare Case of Focal Gigantism of the Foot

Sellvam SA, Raghu S, Leong JF, Hafni F, Abdul Rani R

Cureus, 2023 Aug;15(8):e43173.
PMID: 37692627 DOI: 10.7759/cureus.43173

Macrodystrophia lipomatosa (MDL) is a rare congenital variant of focused gigantism that is non-hereditary. Typically, MDL presents with localized gigantism in either the hand or foot. In this case report, we present the unique instance of a 12-year-old girl who has experienced enlargement of the first and second toes on her right foot since birth. Plain radiographs and MRI findings revealed the accumulation of fatty tissue around the first and second toes, medial and lateral aspects of the first metatarsal, extending up to the medial plantar arch of the foot. To enhance foot functionality and alleviate any issues with wearing footwear, a successful reconstruction surgical intervention was performed. As a result, the patient can now wear shoes without any difficulties. MDL is a very uncommon kind of congenital localised gigantism, and surgical consultation is frequently performed for cosmetic reasons.
Fulltext Scaphoid Plate Osteosynthesis in Complex Fractures and Wrist Trauma: A Case Series

Liau CJ, Liew SK, Arsad SR, Muhammad Nawawi RF, Silvanathan JP

Cureus, 2023 Sep;15(9):e45067.
PMID: 37842372 DOI: 10.7759/cureus.45067

Introduction Treatment of scaphoid fracture is challenging due to its unique blood supply and geometry. Traditionally, a headless compression screw is the standard treatment for unstable scaphoid fracture. Some fractures are complex, for example, comminution with bone loss. A scaphoid plate is an option in these difficult fractures providing adequate rotational stability. Aim To share our experience in using scaphoid plates in complex wrist trauma and comminuted fractures. Method and material Complex wrist trauma involving scaphoid fractures that were comminuted and multi-fragmentary fractures treated with plate osteosynthesis were retrospectively reviewed between July 2019 and September 2021. Patient demographic data, preoperative radiographs, CT scans, pain, wrist range of motion, and fracture union rate to union were reviewed. Quick Disabilities of the Arm, Shoulder, and Hand (QuickDASH®) score was recorded at 1-year postoperative follow-up. Results Nine patients associated with complex wrist trauma were included in this case series. The mean follow-up was 2.5 years (13-30 months). The union rate was 100%. The mean arc of motion was 105° (95-110°). QuickDASH® score was 19.96 at 1-year postoperative follow-up. Four patients had good outcomes, four satisfactory, and one poor outcome. One hardware complication was observed which was the impingement of the plate proximally over the articular surface of the distal radius. Conclusion A scaphoid plate is a reliable option for treating complex and difficult fractures. It provides adequate stability, especially in comminution, bone loss, or multi-fragmentary fractures which are not amendable using other fixation methods. We recommend the expansion of plate osteosynthesis beyond scaphoid nonunion into complex wrist trauma.
Fulltext Level and determinants of knowledge of symptomatic knee osteoarthritis among railway workers in Malaysia

Ganasegeran K, Menke JM, Challakere Ramaswamy VM, Abdul Manaf R, Alabsi AM, Al-Dubai SA

Biomed Res Int, 2014;2014:370273.
PMID: 24701573 DOI: 10.1155/2014/370273

BACKGROUND: Symptomatic knee osteoarthritis, an ancient malady greatly impairing modern population quality of life, has stimulated global attention to find effective modes of prevention and intervention.
PURPOSE: This study aimed to assess factors affecting knowledge of symptomatic knee osteoarthritis (knee OA) among Malaysian railway workers.
METHODS: A cross-sectional study was conducted among 513 railway workers involving eight major states within Peninsular Malaysia using population-based sampling. The assessment instrument was a face-validated, prepiloted, self-administered instrument with sociodemographics and knowledge items on knee OA.
RESULTS: Mean (± SD) age of the respondents was 41.4 (± 10.7), with the majority aged 50 years or older (34.9%). Of the total respondents, 53.6% had low levels of knowledge of knee OA disease. Multivariate analysis found that four demographic predictors, age ≥ 50 years, family history of knee OA, self-awareness, and clinical diagnosis of the disease entity, were significantly associated with knowledge scores.
CONCLUSION: The finding of a low level knee OA knowledge among Malaysian railway workers points to an urgent need for massive information to be disseminated among the workers at risk to foster primary prevention and self-care.
Aortic root pseudoaneurysm: a case report and literature review

Manokaran P, Krishnasamy S, Aman RRABR, Teoh VWY, Loch A

Indian J Thorac Cardiovasc Surg, 2024 Jan;40(1):68-77.
PMID: 38125320 DOI: 10.1007/s12055-023-01580-x

Pseudoaneurysms of the aortic root are rare. A case of prosthetic aortic valve infection progressing from a confined intramural abscess to a ruptured abscess communicating with the aorta and forming a large pseudoaneurysm is described. Additionally, data from all cases and case series, published between 2000 and 2021, was analyzed. A PUBMED search for the keywords "aortic root mycotic aneurysm," "aortic root abscess AND infective endocarditis," and "aortic root mycotic aneurysm AND infective endocarditis" yielded 152 publications (with 157 cases described): Aortic pseudoaneurysm is more common in males (80.9%, n = 127). Mean age is 51 years (4 months-84 years). The most common symptom is fever (68.5%, n = 102). Mean time until diagnosis is 27.2 days. Embolic complications are present in 17.8% (n = 28) at diagnosis. Most cases are due to valvular infections (n = 72 cases, 45.9%). Prior cardiac surgery is documented in 49.0% (n = 77). The mean time interval for developing aortic root abscess following heart surgery is 32.2 months. 22.3% (n = 35) are immunocompromised. Aetiological agents were Staphylococcus sp. (34.1%, n = 47) and Streptococcus sp. (23.2%, n = 32). Mean antimicrobial therapy lasts 58.5 days. Outcome with surgery is superior to medical treatment: overall inpatient mortality 18.5% (n = 27); with surgery 12.2% (n = 15 out of 123 patients), with only medical management 47.8% (n = 11 out of 23 patients). In conclusion, aortic root pseudoaneurysm occurs most commonly in middle-aged male patients. History of prior aortic procedures is commonly present. Correct diagnosis hinges on detailed history, transoesophageal echocardiography, and computed tomography (CT) aorta. Surgery is the preferred therapeutic option.
SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s12055-023-01580-x.
GIS-Based Assessments of Neighborhood Food Environments and Chronic Conditions: An Overview of Methodologies

Ganasegeran K, Abdul Manaf MR, Safian N, Waller LA, Abdul Maulud KN, Mustapha FI

Annu Rev Public Health, 2023 Dec 07.
PMID: 38061019 DOI: 10.1146/annurev-publhealth-101322-031206

The industrial revolution and urbanization fundamentally restructured populations' living circumstances, often with poor impacts on health. As an example, unhealthy food establishments may concentrate in some neighborhoods and, mediated by social and commercial drivers, increase local health risks. To understand the connections between neighborhood food environments and public health, researchers often use geographic information systems (GIS) and spatial statistics to analyze place-based evidence, but such tools require careful application and interpretation. In this article, we summarize the factors shaping neighborhood health in relation to local food environments and outline the use of GIS methodologies to assess associations between the two. We provide an overview of available data sources, analytical approaches, and their strengths and weaknesses. We postulate next steps in GIS integration with forecasting, prediction, and simulation measures to frame implications for local health policies. Expected final online publication date for the Annual Review of Public Health, Volume 45 is April 2024. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
Interaction mechanism of a cysteine protease inhibitor, odanacatib, with human serum albumin: In vitro and bioinformatics studies

Asngari NJM, Bakar KA, Feroz SR, Razak FA, Halim AAA

Biophys Chem, 2024 Feb;305:107140.
PMID: 38118338 DOI: 10.1016/j.bpc.2023.107140

Odanacatib (ODN) is a selective cathepsin K inhibitor that acts as an anti-resorptive agent to treat osteoporosis. ODN is also found effective in reducing the effect of severe periodontitis. The interaction between ODN and human serum albumin (HSA) was investigated using spectroscopic, microscopic, and in silico approaches to characterize their binding. The fluorescence intensity of HSA increased upon the addition of increasing concentrations of ODN accompanied by blueshift in the fluorescence spectrum, which suggested hydrophobic formation around the microenvironment of the fluorophores upon ODN binding. A moderate binding affinity was obtained for ODN-HSA binding, with binding constant (Ka) values of ∼104 M-1. Circular dichroism results suggested that the overall secondary and tertiary structures of HSA were both only slightly altered upon ODN binding. The surface morphology of HSA was also affected upon ODN binding, showing aggregate formation. Drug displacement and molecular docking results revealed that ODN preferably binds to site III in subdomain IB of HSA, while molecular dynamics simulations indicated formation of a stable protein complex when site III was occupied by ODN. The ODN-HSA complex was mainly stabilized by a combination of hydrogen bonding, hydrophobic interactions, and van der Waals forces. These findings provide additional information to understand the interaction mechanism of ODN in blood circulation and may help in future improvements on the adverse effects of ODN.
Are Malaysian Diabetic Patients Ready to Use The New Generation of Health Care Service Delivery? A Telehealth Interest Assessment

Samiei V, Wan Puteh SE, Abdul Manaf MR, Abdul Latip K, Ismail A

Malays J Med Sci, 2016 Mar;23(2):44-52.
PMID: 27547114 MyJurnal

BACKGROUND: The idea of launching an internet-based self-management program for patients with diabetes led us to do a cross-sectional study to find out about the willingness, interest, equipment, and level of usage of computer and internet in a medium- to low-social class area and to find the feasibility of using e-telemonitoring systems for these patients.
METHODS: A total of 180 patients with type 2 diabetes participated in this study and fulfilled the self-administered questionnaire in Diabetes Clinic of Primary Medical Center of University Kebangsaan Malaysia Medical Centre; the response rate was 84%. We used the universal sampling method and assessed three groups of factors including sociodemographic, information and communication technology (ICT), willingness and interest, and disease factors.
RESULTS: Our results showed that 56% of the patients with diabetes were interested to use such programs; majority of the patients were Malay, and patients in the age group of 51-60 years formed the largest group. Majority of these patients studied up to secondary level of education. Age, education, income, and money spent for checkup were significantly associated with the interest of patients with diabetes to the internet-based programs. ICT-related factors such as computer ownership, computer knowledge, access to the internet, frequency of using the internet and reasons of internet usage had a positive effect on patients' interest.
CONCLUSION: Our results show that among low to intermediate social class of Malaysian patients with type 2 diabetes, more than 50% of them can and wanted to use the internet-based self-management programs. Furthermore, we also show that patients equipped with more ICT-related factors had more interest toward these programs. Therefore, we propose making ICT more affordable and integrating it into the health care system at primary care level and then extending it nationwide.
Fulltext Isolation of Textile Waste Cellulose Nanofibrillated Fibre Reinforced in Polylactic Acid-Chitin Biodegradable Composite for Green Packaging Application

Rizal S, Olaiya FG, Saharudin NI, Abdullah CK, N G O, Mohamad Haafiz MK, et al.

Polymers (Basel), 2021 Jan 20;13(3).
PMID: 33498323 DOI: 10.3390/polym13030325

Textile waste cellulose nanofibrillated fibre has been reported with excellent strength reinforcement ability in other biopolymers. In this research cellulose nanofibrilated fibre (CNF) was isolated from the textile waste cotton fabrics with combined supercritical carbon dioxide and high-pressure homogenisation. The isolated CNF was used to enhance the polylactic acid/chitin (PLA/chitin) properties. The properties enhancement effect of the CNF was studied by characterising the PLA/chitin/CNF biocomposite for improved mechanical, thermal, and morphological properties. The tensile properties, impact strength, dynamic mechanical analysis, thermogravimetry analysis, scanning electron microscopy, and the PLA/chitin/CNF biocomposite wettability were studied. The result showed that the tensile strength, elongation, tensile modulus, and impact strength improved significantly with chitin and CNF compared with the neat PLA. Furthermore, the scanning electron microscopy SEM (Scanning Electron Microscopy) morphological images showed uniform distribution and dispersion of the three polymers in each other, which corroborate the improvement in mechanical properties. The biocomposite's water absorption increased more than the neat PLA, and the contact angle was reduced. The results of the ternary blend compared with PLA/chitin binary blend showed significant enhancement with CNF. This showed that the three polymers' combination resulted in a better material property than the binary blend.
Fulltext Functional Properties and Molecular Degradation of Schizostachyum Brachycladum Bamboo Cellulose Nanofibre in PLA-Chitosan Bionanocomposites

Rizal S, Saharudin NI, Olaiya NG, Khalil HPSA, Haafiz MKM, Ikramullah I, et al.

Molecules, 2021 Apr 01;26(7).
PMID: 33916094 DOI: 10.3390/molecules26072008

The degradation and mechanical properties of potential polymeric materials used for green manufacturing are significant determinants. In this study, cellulose nanofibre was prepared from Schizostachyum brachycladum bamboo and used as reinforcement in the PLA/chitosan matrix using melt extrusion and compression moulding method. The cellulose nanofibre(CNF) was isolated using supercritical carbon dioxide and high-pressure homogenisation. The isolated CNF was characterised with transmission electron microscopy (TEM), FT-IR, zeta potential and particle size analysis. The mechanical, physical, and degradation properties of the resulting biocomposite were studied with moisture content, density, thickness swelling, tensile, flexural, scanning electron microscopy, thermogravimetry, and biodegradability analysis. The TEM, FT-IR, and particle size results showed successful isolation of cellulose nanofibre using this method. The result showed that the physical, mechanical, and degradation properties of PLA/chitosan/CNF biocomposite were significantly enhanced with cellulose nanofibre. The density, thickness swelling, and moisture content increased with the addition of CNF. Also, tensile strength and modulus; flexural strength and modulus increased; while the elongation reduced. The carbon residue from the thermal degradation and the glass transition temperature of the PLA/chitosan/CNF biocomposite was observed to increase with the addition of CNF. The result showed that the biocomposite has potential for green and sustainable industrial application.
Fulltext Extraction of Cellulose Nanofibers via Eco-friendly Supercritical Carbon Dioxide Treatment Followed by Mild Acid Hydrolysis and the Fabrication of Cellulose Nanopapers

Atiqah MSN, Gopakumar DA, F A T O, Pottathara YB, Rizal S, Aprilia NAS, et al.

Polymers (Basel), 2019 Nov 05;11(11).
PMID: 31694184 DOI: 10.3390/polym11111813

The conventional isolation of cellulose nanofibers (CNFs) process involves high energy input which leads to compromising the pulp fiber's physical and chemical properties, in addition to the issue of elemental chlorine-based bleaching, which is associated with serious environmental issues. This study investigates the characteristic functional properties of CNFs extracted via total chlorine-free (TCF) bleached kenaf fiber followed by an eco-friendly supercritical carbon dioxide (SC-CO2) treatment process. The Fourier transmission infra-red FTIR spectra result gave remarkable effective delignification of the kenaf fiber as the treatment progressed. TEM images showed that the extracted CNFs have a diameter in the range of 10-15 nm and length of up to several micrometers, and thereby proved that the supercritical carbon dioxide pretreatment followed by mild acid hydrolysis is an efficient technique to extract CNFs from the plant biomass. XRD analysis revealed that crystallinity of the fiber was enhanced after each treatment and the obtained crystallinity index of the raw fiber, alkali treated fiber, bleached fiber, and cellulose nanofiber were 33.2%, 54.6%, 88.4%, and 92.8% respectively. SEM images showed that amorphous portions like hemicellulose and lignin were removed completely after the alkali and bleaching treatment, respectively. Moreover, we fabricated a series of cellulose nanopapers using the extracted CNFs suspension via a simple vacuum filtration technique. The fabricated cellulose nanopaper exhibited a good tensile strength of 75.7 MPa at 2.45% strain.
Fulltext The Role of Two-Step Blending in the Properties of Starch/Chitin/Polylactic Acid Biodegradable Composites for Biomedical Applications

Olaiya NG, Nuryawan A, Oke PK, Khalil HPSA, Rizal S, Mogaji PB, et al.

Polymers (Basel), 2020 Mar 05;12(3).
PMID: 32151004 DOI: 10.3390/polym12030592

The current research trend for excellent miscibility in polymer mixing is the use of plasticizers. The use of most plasticizers usually has some negative effects on the mechanical properties of the resulting composite and can sometimes make it toxic, which makes such polymers unsuitable for biomedical applications. This research focuses on the improvement of the miscibility of polymer composites using two-step mixing with a rheomixer and a mix extruder. Polylactic acid (PLA), chitin, and starch were produced after two-step mixing, using a compression molding method with decreasing composition variation (between 8% to 2%) of chitin and increasing starch content. A dynamic mechanical analysis (DMA) was used to study the mechanical behavior of the composite at various temperatures. The tensile strength, yield, elastic modulus, impact, morphology, and compatibility properties were also studied. The DMA results showed a glass transition temperature range of 50 °C to 100 °C for all samples, with a distinct peak value for the loss modulus and factor. The single distinct peak value meant the polymer blend was compatible. The storage and loss modulus increased with an increase in blending, while the loss factor decreased, indicating excellent compatibility and miscibility of the composite components. The mechanical properties of the samples improved compared to neat PLA. Small voids and immiscibility were noticed in the scanning electron microscopy images, and this was corroborated by X-ray diffraction graphs that showed an improvement in the crystalline nature of PLA with starch. Bioabsorption and toxicity tests showed compatibility with the rat system, which is similar to the human system.
Long-term evaluation of osteoarthritis sheep knee, treated with TGF-β3 and BMP-6 induced multipotent stem cells

Ude CC, Shamsul BS, Ng MH, Chen HC, Ohnmar H, Amaramalar SN, et al.

Exp Gerontol, 2018 04;104:43-51.
PMID: 29421350 DOI: 10.1016/j.exger.2018.01.020

BACKGROUND: Hyaline articular cartilage, which protects the bones of diarthrodial joints from forces associated with load bearing, frictions, and impacts has very limited capacities for self-repair. Over the years, the trend of treatments has shifted to regenerations and researchers have been on the quest for a lasting regeneration. We evaluated the treatment of osteoarthritis by chondrogenically induced ADSCs and BMSCs for a long time functional recovery.
METHODS: Osteoarthritis was induced at the right knee of sheep by complete resection of ACL and medial meniscus. Stem cells from sheep were induced to chondrogenic lineage. Test sheep received 5 mls single doses of 2 × 107 autologous PKH26-labelled ADSCs or BMSCs, while controls received basal medium. Functional recovery of the knees was evaluated via electromyography.
RESULTS: Induced ADSCs had 625, 255, 393, 908, 409, 157 and 1062 folds increases of collagen I, collagen II, aggrecan, SOX9, cartilage oligomeric protein, chondroadherin and fibromodullin compare to uninduced cells, while BMSCs had 702, 657, 321, 276, 337, 233 and 1163 respectively; p = .001. Immunocytochemistry was positive for these chondrogenic markers. 12 months post-treatment, controls scored 4 in most regions using ICRS, while the treated had 8; P = .001. Regenerated cartilages were positive to PKH26 and demonstrated the presence of condensing cartilages on haematoxylin and eosin; and Safranin O. OA degenerations caused significant amplitude shift from right to left hind limb. After treatments, controls persisted with significant decreases; while treated samples regained balance.
CONCLUSIONS: Both ADSCs and BMSCs had increased chondrogenic gene expressions using TGF-β3 and BMP-6. The treated knees had improved cartilage scores; PKH26 can provide elongated tracking, while EMG results revealed improved joint recoveries. These could be suitable therapies for osteoarthritis.

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